JIS Flanges
JIS Flange: Specifications | Materials | Dimensions | Weight Chart | Tolerances | FAQ
JIS Flanges Manufacturer and Supplier in Japan, USA, Germany, UAE, India, and South Korea, offering Weld Neck, Slip-On, Blind, Threaded, and Lap Joint flanges in Carbon, Stainless, and Alloy Steel as per JIS B2220 standards. Available in sizes DN 15 (1/2") to DN 1200 (48") with pressure ratings PN 6 to PN 40, ideal for industrial piping systems.
Best Export Prices: sales@midlandforgefittings.com
Midland Forge Fittings is a leading manufacturer and supplier of JIS Flanges, serving clients globally. With years of experience in the industry, we specialize in delivering high-quality flanges and fittings that meet strict JIS B2220 standards for durability, precision, and reliability. Our solutions cater to oil & gas, petrochemical, power plant, and industrial piping systems.
We use state-of-the-art forging and CNC machining techniques to produce JIS flanges with precise dimensions and uniform quality. Each flange undergoes hot forging, lathe machining, and surface finishing, ensuring accurate bolt alignment, smooth flange faces, and stress-free connections. Our manufacturing methods guarantee high mechanical strength and resistance to pressure and temperature variations.
Quality is at the core of our operations. Every JIS B2220 Flange is subjected to rigorous material verification, dimensional checks, and tolerance inspection to ensure compliance with international standards. Additional tests such as hydrostatic pressure testing, NDT, and surface inspection are performed depending on customer requirements. This ensures that our flanges deliver leak-proof performance and long-term reliability.
Our JIS Flanges include Weld Neck, Slip-On, Blind, Threaded, and Lap Joint types, available in Carbon Steel, Stainless Steel, and Alloy Steel. They cover a size range from DN 15 (1/2″) to DN 1200 (48″) with pressure ratings PN 6 to PN 40, suitable for high-pressure, high-temperature, and corrosive environments. Designed for industrial, petrochemical, and power plant applications, these flanges feature Raised Face (RF) or Flat Face (FF) designs for perfect gasket sealing and uniform stress distribution.
We prioritize safe handling and delivery of our products. Each JIS Weld Neck flange is carefully cleaned, coated, and packed using industrial-grade wooden crates, pallets, and protective materials to prevent corrosion and transit damage. Our logistics network covers global shipping, ensuring products reach USA, Germany, UAE, India, Japan, South Korea, and other international destinations on time. We partner with trusted carriers to guarantee secure and timely delivery.
JIS Slip-On flange - Specifications
JIS Blind flange - Materials, Grades & Standards
| Material | Grade / Standard |
Application / Notes |
|---|---|---|
| Carbon Steel | St3, S235JR, S275JR | Suitable for general industrial and low-to-medium pressure pipelines |
| Stainless Steel | 12X18H10T (EN 1.4301), 08X17H13M2 (EN 1.4404) |
Corrosion-resistant, high-temperature applications |
| Alloy Steel | 15CrMo, 10CrMo9-10 | High-strength, high-pressure pipelines in chemical and petrochemical industries |
| Duplex / Super Duplex | 1.4462 (UNS S31803), 1.4410 (UNS S32750) |
Highly resistant to corrosion and suitable for aggressive environments |
| Nickel Alloys | Inconel 625, Incoloy 825 | Specialized applications requiring high temperature and chemical resistance |
JIS B2220 Weld Neck Flange – Dimensions (DN 15 to DN 1200)
| Nominal Size (DN / Inch) |
Outside Diameter (OD, mm) |
Bolt Circle Diameter (BCD, mm) |
Number of Bolts |
Bolt Diameter (mm) |
Flange Thickness (mm) |
|---|---|---|---|---|---|
| DN 15 / 1/2″ | 95 | 65 | 4 | 14 | 14 |
| DN 20 / 3/4″ | 105 | 75 | 4 | 14 | 14 |
| DN 25 / 1″ | 115 | 85 | 4 | 14 | 14 |
| DN 32 / 1 1/4″ | 140 | 100 | 4 | 14 | 16 |
| DN 40 / 1 1/2″ | 150 | 110 | 4 | 14 | 16 |
| DN 50 / 2″ | 165 | 125 | 4 | 14 | 16 |
| DN 65 / 2 1/2″ | 185 | 145 | 4 | 18 | 18 |
| DN 80 / 3″ | 200 | 160 | 8 | 18 | 18 |
| DN 100 / 4″ | 220 | 180 | 8 | 18 | 20 |
| DN 150 / 6″ | 285 | 240 | 8 | 22 | 22 |
| DN 200 / 8″ | 340 | 295 | 12 | 22 | 24 |
| DN 250 / 10″ | 395 | 350 | 12 | 26 | 26 |
| DN 300 / 12″ | 445 | 400 | 12 | 26 | 28 |
| DN 350 / 14″ | 495 | 450 | 16 | 30 | 30 |
| DN 400 / 16″ | 545 | 500 | 16 | 30 | 32 |
| DN 450 / 18″ | 595 | 550 | 16 | 34 | 34 |
| DN 500 / 20″ | 645 | 600 | 20 | 34 | 36 |
| DN 600 / 24″ | 745 | 700 | 20 | 38 | 38 |
| DN 700 / 28″ | 845 | 800 | 24 | 42 | 42 |
| DN 800 / 32″ | 945 | 900 | 24 | 42 | 46 |
| DN 900 / 36″ | 1045 | 1000 | 28 | 46 | 50 |
| DN 1000 / 40″ | 1145 | 1100 | 28 | 46 | 54 |
| DN 1200 / 48″ | 1345 | 1300 | 32 | 50 | 58 |
JIS B2220 Slip-On Flange – Dimensions (DN 15 to DN 1200)
| Nominal Size (DN / Inch) |
Outside Diameter (OD, mm) |
Bolt Circle Diameter (BCD, mm) |
Number of Bolts |
Bolt Diameter (mm) |
Flange Thickness (mm) |
|---|---|---|---|---|---|
| DN 15 / 1/2″ | 95 | 65 | 4 | 14 | 12 |
| DN 20 / 3/4″ | 105 | 75 | 4 | 14 | 12 |
| DN 25 / 1″ | 115 | 85 | 4 | 14 | 12 |
| DN 32 / 1 1/4″ | 140 | 100 | 4 | 14 | 14 |
| DN 40 / 1 1/2″ | 150 | 110 | 4 | 14 | 14 |
| DN 50 / 2″ | 165 | 125 | 4 | 14 | 14 |
| DN 65 / 2 1/2″ | 185 | 145 | 4 | 18 | 16 |
| DN 80 / 3″ | 200 | 160 | 8 | 18 | 16 |
| DN 100 / 4″ | 220 | 180 | 8 | 18 | 18 |
| DN 150 / 6″ | 285 | 240 | 8 | 22 | 20 |
| DN 200 / 8″ | 340 | 295 | 12 | 22 | 22 |
| DN 250 / 10″ | 395 | 350 | 12 | 26 | 24 |
| DN 300 / 12″ | 445 | 400 | 12 | 26 | 26 |
| DN 350 / 14″ | 495 | 450 | 16 | 30 | 28 |
| DN 400 / 16″ | 545 | 500 | 16 | 30 | 30 |
| DN 450 / 18″ | 595 | 550 | 16 | 34 | 32 |
| DN 500 / 20″ | 645 | 600 | 20 | 34 | 34 |
| DN 600 / 24″ | 745 | 700 | 20 | 38 | 36 |
| DN 700 / 28″ | 845 | 800 | 24 | 42 | 40 |
| DN 800 / 32″ | 945 | 900 | 24 | 42 | 44 |
| DN 900 / 36″ | 1045 | 1000 | 28 | 46 | 48 |
| DN 1000 / 40″ | 1145 | 1100 | 28 | 46 | 52 |
| DN 1200 / 48″ | 1345 | 1200 | 32 | 50 | 56 |
JIS B2220 Blind Flange – Dimensions (DN 15 to DN 1200)
| Nominal Size (DN / Inch) |
Outside Diameter (OD, mm) |
Bolt Circle Diameter (BCD, mm) |
Number of Bolts |
Bolt Diameter (mm) |
Flange Thickness (mm) |
|---|---|---|---|---|---|
| DN 15 / 1/2″ | 95 | 65 | 4 | 14 | 16 |
| DN 20 / 3/4″ | 105 | 75 | 4 | 14 | 16 |
| DN 25 / 1″ | 115 | 85 | 4 | 14 | 16 |
| DN 32 / 1 1/4″ | 140 | 100 | 4 | 14 | 18 |
| DN 40 / 1 1/2″ | 150 | 110 | 4 | 14 | 18 |
| DN 50 / 2″ | 165 | 125 | 4 | 14 | 18 |
| DN 65 / 2 1/2″ | 185 | 145 | 4 | 18 | 20 |
| DN 80 / 3″ | 200 | 160 | 8 | 18 | 20 |
| DN 100 / 4″ | 220 | 180 | 8 | 18 | 22 |
| DN 150 / 6″ | 285 | 240 | 8 | 22 | 24 |
| DN 200 / 8″ | 340 | 295 | 12 | 22 | 26 |
| DN 250 / 10″ | 395 | 350 | 12 | 26 | 28 |
| DN 300 / 12″ | 445 | 400 | 12 | 26 | 30 |
| DN 350 / 14″ | 495 | 450 | 16 | 30 | 32 |
| DN 400 / 16″ | 545 | 500 | 16 | 30 | 34 |
| DN 450 / 18″ | 595 | 550 | 16 | 34 | 36 |
| DN 500 / 20″ | 645 | 600 | 20 | 34 | 38 |
| DN 600 / 24″ | 745 | 700 | 20 | 38 | 40 |
| DN 700 / 28″ | 845 | 800 | 24 | 42 | 44 |
| DN 800 / 32″ | 945 | 900 | 24 | 42 | 46 |
| DN 900 / 36″ | 1045 | 1000 | 28 | 46 | 50 |
| DN 1000 / 40″ | 1145 | 1100 | 28 | 46 | 54 |
| DN 1200 / 48″ | 1345 | 1300 | 32 | 50 | 58 |
JIS Steel flange - Weight Chart
| Nominal Size (DN / Inch) |
Weld Neck (WN) |
Slip-On (SO) |
Blind (BL) |
Threaded (TH) |
Lap Joint (LJ) |
|---|---|---|---|---|---|
| DN 15 / 1/2″ | 1.8 | 1.2 | 2.0 | 1.1 | 1.1 |
| DN 20 / 3/4″ | 2.0 | 1.4 | 2.3 | 1.3 | 1.3 |
| DN 25 / 1″ | 2.4 | 1.6 | 2.7 | 1.5 | 1.5 |
| DN 32 / 1 1/4″ | 3.0 | 2.0 | 3.4 | 1.9 | 1.9 |
| DN 40 / 1 1/2″ | 3.4 | 2.3 | 3.9 | 2.2 | 2.2 |
| DN 50 / 2″ | 4.2 | 2.9 | 4.7 | 2.8 | 2.8 |
| DN 65 / 2 1/2″ | 6.1 | 4.2 | 6.8 | 3.9 | 3.9 |
| DN 80 / 3″ | 7.5 | 5.3 | 8.5 | 4.8 | 4.8 |
| DN 100 / 4″ | 11.0 | 7.6 | 12.5 | 6.7 | 6.7 |
| DN 150 / 6″ | 19.5 | 14.5 | 22.0 | 12.0 | 12.0 |
| DN 200 / 8″ | 33.5 | 24.5 | 38.0 | 21.0 | 21.0 |
| DN 250 / 10″ | 55.0 | 40.0 | 62.5 | 34.5 | 34.5 |
| DN 300 / 12″ | 78.5 | 57.0 | 88.0 | 49.0 | 49.0 |
| DN 350 / 14″ | 110.0 | 80.0 | 125.0 | 70.0 | 70.0 |
| DN 400 / 16″ | 145.0 | 106.0 | 165.0 | 92.0 | 92.0 |
| DN 450 / 18″ | 180.0 | 130.0 | 205.0 | 120.0 | 120.0 |
| DN 500 / 20″ | 230.0 | 165.0 | 260.0 | 150.0 | 150.0 |
| DN 600 / 24″ | 330.0 | 240.0 | 370.0 | 210.0 | 210.0 |
| DN 700 / 28″ | 445.0 | 325.0 | 500.0 | 280.0 | 280.0 |
| DN 800 / 32″ | 580.0 | 420.0 | 655.0 | 365.0 | 365.0 |
| DN 900 / 36″ | 750.0 | 540.0 | 850.0 | 470.0 | 470.0 |
| DN 1000 / 40″ | 950.0 | 685.0 | 1075.0 | 595.0 | 595.0 |
| DN 1200 / 48″ | 1350.0 | 980.0 | 1500.0 | 850.0 | 850.0 |
Carbon, Stainless, Alloy Steel JIS Flanges - Tolerances
| Parameter | Tolerance / Limit |
Applicable Flange Types |
|---|---|---|
| Outside Diameter (OD) | ±2 mm for DN ≤ 300, ±3 mm for DN 350–600, ±4 mm for DN >600 | All flange types (WN, SO, BL, TH, LJ) |
| Bolt Circle Diameter (BCD) | ±1.5 mm for DN ≤ 300, ±2 mm for DN 350–600, ±3 mm for DN >600 | All flange types |
| Number of Bolt Holes | Exact per standard | All flange types |
| Bolt Hole Diameter | ±0.5 mm | All flange types |
| Flange Thickness | ±2 mm for DN ≤ 300, ±3 mm for DN 350–600, ±4 mm for DN >600 | All flange types |
| Out-of-Roundness | ≤1.5% of nominal OD | All flange types |
| Flatness (Face) | ≤1.5 mm for DN ≤ 300, ≤2 mm for DN 350–600, ≤3 mm for DN >600 | All flange types |
| Raised Face Height (if applicable) | ±1 mm | WN, BL, TH, SO flanges |
| Taper of Hub (WN/TH) | ≤1° | Weld Neck, Threaded flanges |
| Surface Finish (Facing) | 3.2–6.3 μm Ra | All flanges |
What are the different types of JIS flanges and their applications?
- Weld Neck (WN) Flanges:
- Feature a tapered hub that reduces stress concentrations at the base of the flange.
- Ideal for high-pressure and high-temperature pipelines, such as steam, oil, and chemical transport systems.
- Welded to the pipe using butt welding, ensuring a permanent, strong joint.
- Slip-On (SO) Flanges:
- The pipe slips into the flange and is welded both inside and outside.
- Suitable for medium-pressure systems and frequent maintenance scenarios.
- Blind (BL) Flanges:
- Used to seal the end of a pipeline or vessel, preventing fluid or gas flow.
- Also serves as a test flange for pressure and leakage tests in piping systems.
- Threaded (TH) Flanges:
- Feature internal threads to connect with threaded pipes, eliminating the need for welding.
- Suitable for low-pressure pipelines and temporary connections.
- Lap Joint (LJ) Flanges:
- Used with stub ends, allowing easy alignment and frequent dismantling.
- Commonly used in corrosion-prone pipelines, as the stub end can be replaced without removing the flange.
What is a JIS flange, Advantages and where is it used?
Definition: JIS (Japanese Industrial Standard) flanges are mechanical components used to connect pipes, valves, pumps, and equipment in a piping system while ensuring a secure, leak-proof joint.
Standards Compliance: Manufactured strictly according to JIS B2220, these flanges conform to dimensional, material, and pressure standards, ensuring reliability in critical systems.
Applications:
- Industrial Piping: Factories, chemical plants, and water treatment systems.
- Oil & Gas: High-pressure pipelines for refineries and offshore platforms.
- Petrochemical: For transporting corrosive fluids and gases.
- Power Plants: Steam, water, and gas pipelines requiring high-temperature resistance.
Advantages: Provides ease of maintenance, interchangeability, and high mechanical strength, making them essential in critical industrial applications.
How to select the right JIS flange for your piping system?
Determine Pipe Size: Choose DN according to pipeline diameter.
Determine Pressure Rating: Select PN rating based on operating conditions.
Select Flange Type:
- Weld Neck: High pressure
- Slip-On: Medium pressure
- Blind: Pipe sealing or testing
- Threaded: Low pressure or temporary connection
- Lap Joint: Frequent dismantling or alignment adjustment
Select Material Grade: Based on corrosion, temperature, and mechanical load.
Check JIS B2220 Compliance: Ensures accuracy, safety, and long-term reliability.